Surfactant modified oils for dust control of loose-fill insulation

ABSTRACT

The present invention serves to substantially improve the dust capture property of dedusting oils, by modifying these oils with nonionic and/or cationic surfactants. The application of surfactant modified oils reduces dust that is generated when loose-fill insulation is installed.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation of U.S. application Ser. No.10/136,008, filed on May 1, 2002.

FIELD OF THE INVENTION

The present invention relates to methods for improving the dust captureproperties of dedusting oils, which properties are useful in themanufacture and installation of loose-fill insulation.

BACKGROUND OF THE INVENTION

Over the past 40 years, many homeowners have begun to install extrainsulation in their attics or crawlspaces in an effort to save money onheating bills. Typically, new construction is thoroughly insulated inaccordance with applicable building codes and industry standards. Acommon form of insulation used by consumers and insulation contractorshas been fiberglass insulation batts and blankets. However, insulationbatts are relatively expensive and may require some cutting and shapingduring installation.

More recently, the use of glass fiber blowing wool or loose-fillinsulation has increased in popularity. Loose-fill, fiberglassinsulation exists in many forms. Bonded and non-bonded loose-fillfiberglass are commonly used terms to describe loose-fill insulationproducts. Bonded loose-fill insulation is derived from blanket or battinsulation which has been made with a thermoset binder. It is producedby either pulverizing or cutting the blanket or batt insulation,compressing the resulting product and packaging it into bags.Non-bonded, loose-fill insulation comprises smaller nodules oftraditional, straight, short fibers which are treated with a dedustingoil, compressed, and packaged into bags. Both bonded and non-bondedloose fill insulations can be installed in attics and sidewalls using apneumatic blowing machine.

Loose-fill insulation is popular with insulation contractors because itcan be easily and quickly applied in both new construction as well as inexisting structures. Further, loose-fill insulation is a relatively lowcost material. However, fiberglass loose-fill insulation is typicallyapplied by contractors rather than homeowners because of the specialblowing equipment needed. Such insulation is typically packaged in largebags weighing e.g., 25-35 lbs.

Cellulose loose-fill insulation is another type of insulation commonlyused by consumers, which is formed from shredded, recycled newspapers.Cellulose insulation is desirable for installation by consumers as it isavailable in smaller packages and is less expensive than most otherforms of loose-fill insulation. However, such insulation is dusty, dirtyand difficult to blow properly, and also requires special blowingequipment to install.

When loose-fill insulations are pneumatically applied, they can be thesource of dust and irritation for the installer. While dedusting oilsare typically applied at the time of manufacture to control this dust,and the installers are advised to wear a dust mask and protective gearto reduce their exposure to dust, the effectiveness of these oils couldbe improved, especially when the oils are applied at low applicationrates (e.g., less than about 2% by weight).

SUMMARY OF THE INVENTION

The purpose of the present invention is to substantially improve thedust capture properties of dedusting oils by modifying these oils withnonionic and/or cationic surfactants. These surfactants may be addedindividually, or in combination to the dedusting oils. The applicationof surfactant modified oils reduces the airborne dust that is generatedwhen loose-fill insulation is installed pneumatically.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention serves to substantially improve the dust captureproperty of dedusting oils, by modifying these oils with effectiveamounts of nonionic or cationic surfactants. In testing of the presentinvention, oils which were modified with various surfactants wereapplied through an oil application system onto non-bonded, loose-fillinsulation, at a preferred amount of approximately 2% by weight usingeither air atomized or hydraulic pressure nozzles. One such oil iscommercially available as Telura™ 720E from Exxon Mobil Corporation. Thenon-bonded, loose-fill material was packaged and tested for its dustgeneration characteristics. When compared to a control material madewith an unmodified paraffin oil with a viscosity of 100 SUS, thenon-bonded, loose-fill product made with the surfactant modified oilexhibited substantially lower dust levels. Furthermore, by the method ofthe present invention, the surfactant modified oils reduce dust levelsof insulation that are produced over a range of fiberizing conditions.

Note that the treatment of the present invention should be applied toloose-fill insulation at a temperature at or above about 80° F.,preferably from about 80-110° F.

The following testing demonstrates that the use of surfactant modifiedoils significantly reduced the airborne dust levels of a sample ofthermal insulation product, as compared to similar insulations made withconventional dedusting oils. Dust levels were measured using themethodology as disclosed in U.S. Pat. Nos. 6,005,662 and 6,122,054,herein incorporated by reference. Two distinct fiberizing conditionswere tested. One condition had a fiber fineness index of 2.9 and theother had a fineness index of 2.65 when measured by ASTM D1488-97standard test method for micronaire reading of cotton fibers. Ingeneral, finer fibers tend to produce more dust.

Table 1 shows the % increase in dust reduction when loose-fillinsulation made with the experimental oils was compared to loose fillinsulation using the standard dedusting oil, Prorex 100 made by ExxonMobil. TABLE 1 % Dust Reduction Measured versus Standard Dust ControlOil (Control) % Oil Fiber Applied to % Increase in Treatment FinenessLoose Fill Dust Reduction Standard Dust Control Oil¹ 2.90 2.00 ControlSurfactant Modified Oil- 2.90 1.90 28% Telura 720E² Standard DustControl Oil¹ 2.65 1.87 Control Surfactant Modified Oil- 2.65 1.87 53%Telura 720E² Surfactant Modified Oil- 2.65 1.80 46% Telura 720E³Standard Oil Modified with a 2.65 1.97 25% Cationic Surfactant⁴¹Prorex ™ 100 Process oil from Exxon Mobil²Telura ™ 702E oil modified with glycerol monooleate at 2% by weight³Telura ™ 702E oil modified with glycerol monooleate at 1% by weight⁴Prorex ™ 100 Process Oil modified with an oil containing a quaternaryammonium compound

As noted above, in a preferred embodiment of the present invention, thesurfactant 10 modified oil tested was a standard dust control oil,modified to include 2% by weight of glycerol monooleate, a nonionicsurfactant. Percents by weight of surfactant may range from about0.5-10%. It is anticipated that alternative nonionic surfactants wouldalso be effective, e.g., mono-, di-, and tri-fatty acid esters ofglycerol and modified esters of this type, so long as effective amountsof such surfactants were applied.

In a preferred embodiment of the present invention, the nonionicsurfactant is a monoester of an unsaturated or saturated acid. Theunsaturated acid may be e.g., linoleic or linolenic acid. The saturatedacid may be e.g., a C12 to C18 lauric, myristic, palmitic or stearicacid. In a further preferred embodiment, the nonionic surfactant is adiester or triester of an unsaturated or saturated acid.

As it relates to the loose-fill insulation, it is preferred that themodified oil be applied to the loose-fill insulation at from about0.5-2.5% by weight, with an amount of about 2.0% by weight particularlypreferred.

While this invention has been described with respect to particularembodiments thereof, it is apparent that numerous other forms andmodifications of this invention will be obvious to those skilled in theart. The appended claims and this invention generally should beconstrued to cover all such obvious forms and modifications which arewithin the true spirit and scope of the present invention.

1. A method of controlling dust formation in loose-fill insulation,comprising: applying to said loose-fill insulation dedusting oilmodified with an additive consisting essentially of a surfactant of anamount to control dust formation while the loose-fill insulation is in afiberized state adapted for pneumatic installation.
 2. The method asrecited in claim 1, wherein said combination is applied to saidloose-fill insulation in an amount of from about 0.5-2.5% by weight. 3.The method as recited in claim 1, wherein said surfactant is nonionic.4. The method as recited in claim 1, wherein said surfactant iscationic.
 5. The method as recited in claim 1, wherein said insulationis installed pneumatically.
 6. The method as recited in claim 3, whereinsaid surfactant is glycerol monooleate.
 7. The method is recited inclaim 1, wherein said combination is applied to said loose-fillinsulation in an amount of about 2% by weight.
 8. The method as recitedin claim 3 wherein said nonionic surfactant is a monoester of anunsaturated or saturated acid.
 9. The method as recited in claim 8wherein said unsaturated acid is linoleic or linolenic acid.
 10. Themethod as recited in claim 8 wherein said saturated acid is a C12 to C18lauric, myristic, palmitic to stearic acid.
 11. The method as recited inclaim 3 wherein said nonionic surfactant is a diester or triester of anunsaturated or saturated acid.
 12. A method of controlling dustformation in loose-fill insulation, comprising: applying to saidloose-fill insulation dedusting oil modified with an additive consistingessentially of a nonionic surfactant of an amount to control dustformation while the loose-fill insulation is in a fiberized stateadapted for pneumatic installation.
 13. The method as recited in claim12, wherein said insulation is installed pneumatically.
 14. The methodas recited in claim 13, wherein said combination is applied to saidloose-fill insulation in an amount of from about 1.5-2.5% by weight. 15.The method as recited in claim 13, wherein said nonionic surfactant isglycerol monooleate.
 16. The method as recited in claim 12 wherein saidnonionic surfactant is a monoester of an unsaturated or saturated acid.17. The method as recited in claim 13 wherein said unsaturated acid islinoleic or linolenic acid.
 18. The method as recited in claim 13wherein said saturated acid is a C12 to C18 lauric, myristic, palmiticto stearic acid.
 19. The method as recited in claim 12 wherein saidnonionic surfactant is a diester or triester of an unsaturated orsaturated acid.